While I respect your goal to establish a good sized data set ( /salute ) maybe instead use creative mode in single player to re-create your base, then run 10-20 purges a Level 1 to see what results you get there.
That might be a less time intensive method of confirming or denying that your results are related to the difficulty settings on your group server.
Your method is good, obviously I’m not criticizing it, just trying to think of a way you could spend less time to arrive at an answer.